SplitStream bars and more

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I saw this SplitStream aerobar design in the summer copy of Innovation, the IDSA quarterly magazine, which I received last week. The design by Stanford design student David Baggeroer was featured because it won a second place prize in the Dyson and IDSA sponsored Eye for Why competition. Instead of having two main hand positions like most aerobars that are used for time trails or triathlons, the SplitStream has a hinge that allows the bars to switch from wide to aero position on the fly. Having just completed a local time trial the day before I received the issue, I have to say this moving aerobar concept initially made me a bit nervous. I put a lot more torque on my bar during a race against the clock than I would on a normal ride, so I don’t know how I feel about a hinge in the center. Switching from the aero position to the outer hand position is not difficult with existing bar set ups, so the only possible advantages I can see from this concept are; 1) improved aerodynamics from removing the outer wings when they aren’t being used, and 2) the availability of brake levers and shifters in either position. Looking for more information about this design concept, I noticed a discussion about it on the Core77 forum. A few of the forum posts are pretty hard on the design, but I agree with the people who thought a prototype would be needed to really prove it out. Like many of the people on the Core thread, I am a bit skeptical, but I think the idea probably has some merit as a concept. I would love to see the designer make a prototype, try it out, and refine it further.

Update 7/15/08: Dave B., the designer of this concept commented with more information. Apparently he did make a working prototype, which you can see at a post on his blog. Check out his post for additional renderings, drawings, and explanation of the concept as well.

Several people sent me a link to this Gizmodo post about a folding bike transforms into a backpack. I don’t know what else I can add to that post, but I will mention that I saw the link at Cyclelicious as well.

Last week, Devin from CLIX sent me some information about their product. Basically, CLIX is a quick release system that is designed to be fool proof. The best way to see how it works is to watch the video on their website that shows a wheel removal and reinstallation. When I worked as a bike mechanic many years ago, I remember quite a few bikes coming though the shop in which the quick release lever had been twisted on like a wing nut and the cam was not closed. Though I would bet everyone reading this knows how to properly operate a quick release, there are many people out there who do not, so I am happy to see a design that aims to make the process more intuitive. I would love to try it out for myself, but at first glance it looks like a good solution to me. For more on CLIX, take a look at a post last week on Mountain Biking by 198.

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10 Comments

  1. Robb Sutton (198) July 14, 2008 at 1:47 pm -  Reply

    Come down and ride Blankets when I get mine in…you can help me with the testing.

  2. C July 14, 2008 at 2:22 pm -  Reply

    You can have the bars pivot and still be strong enough. Anyone who doubts this needs to look no further than the aviation field. There have been several high performance aircraft which featured swinging wings including the F-14 Tomcat, the Tornado, and the FB-111. If a plane can have swinging wings and still pull 7g with a few thousand pounds of ordnance hanging off them it’s a safe bet they can make a pivoting handlebar. Of course the weight would be a whole different issue.

  3. Will July 14, 2008 at 3:33 pm -  Reply

    You don’t see variable geometry wings in new aircraft design because the weight and maintenance penalty for those aircraft outweighed the benefits of the design. All but the Tornado have been retired and the B-1 is on its way out as well.

    As for quick-release…it’s time for something better on the front. I’ve been very happy with the new thru-axle front forks on the mountain bike side (and Leftys too) and would like to see something like that on the road. Why have a huge 1.5″ head tube if you are still constrained by such a small clamping interface at the hub?

    Bottom Line…I wish the UCI would change its rulebook to allow for more innovation.

  4. DaveB July 15, 2008 at 3:49 am -  Reply

    Hey James,
    Thanks for the feedback. Love your blog btw. I was surprised to see the handlebars on it. I just got the IDSA magazine today. Unfortunately, they didn’t choose the best images to describe the project. Check out my web site http://www.davebags.com/splitstream to see some more details. A video there shows a quick clip of a functional prototype. It took a while to get the whole concept working on a real bike…lots of iterations and failed prototypes. No trips to the ER yet. I started out just getting the mechanism to work with some 2-d prototypes (rough wood and then lasercam’d acrylic) and then worked my way up to a few sets made out of ABS plastic (CNC mill and FDM machine using CAD/CAM)

    The bars in the video are sturdy enough to ride around campus and helped me get a feel for the mechanism in action. The concept is a little crazy and the execution still needs several more iterations but they’re pretty fun to ride. I thought they would be super squirrelly especially while in transition but the motion is surprisingly stable. When you engage the aero position it’s a bit of a rush.

    Not sure if they’ll ever make it to market or satisfy the requirements of the pros but that wasn’t my goal. School is a great time to try out ridiculous ideas. The project was a lot of fun and a great learning experience. The award was a nice unexpected bonus.
    -Dave

  5. C July 15, 2008 at 2:37 pm -  Reply

    “You don’t see variable geometry wings in new aircraft design because the weight and maintenance penalty for those aircraft outweighed the benefits of the design. All but the Tornado have been retired and the B-1 is on its way out as well.”

    That was kind of the point in my last sentence.

    Also the B-1 is hardly on its way out. A B-1 just saved the lives of a bunch of buys in Afghanistan this weekend. It’s a primary on-call platform for Afghanistan. It’s also being upgraded this summer with the addition of the Sniper pod. Hardly on its way out.

  6. James July 15, 2008 at 3:16 pm -  Reply

    Thanks for the comments everyone; great discussion

    Dave, thanks for leaving a comment. It is great to see the additional renderings, drawings, and (most importantly) the prototype on your blog. I’ll update the post with your link for those who don’t read the comments sections.

  7. bikesgonewild July 15, 2008 at 6:03 pm -  Reply

    …i’m impressed…daveb‘s concept is great & it’s the thinking behind it all that’s impressive…quite simply, to me, it’s a “why not ???” kind of idea…

    …keep conceptualizing, refining & prototyping, daveb…despite the number of articulating pivots involved, if you can make it foolproof & yet light enough, it seems like an idea that will eventually “spread it’s wings”…props…

  8. Art July 16, 2008 at 7:46 am -  Reply

    I can’t think of any reason why those bars wouldn’t be feasible with the right locking mechanism. There should be enough aero advantage to override any weight penalty.

  9. Fritz July 17, 2008 at 5:36 pm -  Reply

    I was very skeptical of CLIX at first but then I played around with one a little and I’m now sold on the concept. Way better and faster than the standard “lawyer lips” IMO. When I last talked with them they had no plans for aftermarket distribution — can you ask if they’ve thought about that some?

    As always, thanks for the link.

  10. jimmythefly July 21, 2008 at 10:02 pm -  Reply

    Hey, DaveB I was one of the guys who was extremely skeptical over on Core77 (haven’t been back since, maybe you’ve posted there, too?). So, I hearby eat my words, because having aprototype changes everything. Anyhows, kudos on the design and especially on the working prototype, what a great example of the media missing important bits of the story!

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